New energy heavy truck central driving box and gear shifting control method thereof

Abstract

A new energy heavy truck central driving box comprises a motor, an input shaft, an intermediate shaft meshed with the input shaft and an output shaft, and is characterized by further comprising a single-stage planet row, a first gear shifting assembly and a second gear shifting assembly, the intermediate shaft and the input shaft are parallel and symmetrically distributed with the input shaft as the center, and a planet carrier of the single-stage planet row and the output shaft are coaxially fixed; the single-stage planet row is connected with the input shaft or the intermediate shaft along with gear shifting of the first gear shifting assembly, the single-stage planet row forms high-torque low-speed or low-torque high-speed output along with gear shifting of the second gear shifting assembly, and the input shaft, the single-stage planet row and the output shaft are coaxially aligned from front to back. The power requirements of the heavy truck under various working conditions such as light load, heavy load, flat road and ramp are met, the single-shaft torque load is reduced, the transmission efficiency is improved, redundant design is formed by multiple intermediate shafts, the gearbox failure risk is reduced, the structural compactness of the driving box is improved, and the driving box is matched with chassis arrangement of the new energy heavy truck. The invention further provides a gear shifting control method of the central driving box of the new energy heavy truck.

Description

Technical Field

[0001] The invention relates to a central drive box of a new energy heavy-duty truck and a gear shift control method thereof, belonging to the technical field of new energy heavy-duty trucks. Background Art

[0002] Medium and heavy-duty trucks need to provide both high drive torque in the constant torque range and high speed in the constant power range to meet the requirements of vehicle acceleration and climbing. Therefore, medium and heavy-duty trucks, which have relatively high requirements for load-bearing torque and focus on economy, generally use motor + gearbox as a pure electric powertrain system technology solution to meet the vehicle's requirements for speed range and torque capacity. At present, the electrification of commercial vehicles lags significantly behind the passenger car industry in terms of transmission efficiency, integration, and weight reduction. The main pain points for the electrification of heavy-duty commercial vehicles are as follows: 1. Most of the current commercial vehicles are driven by a single motor. The main problem of single-motor commercial vehicles is their endurance, which cannot meet the long-distance needs of commercial vehicles. This is directly related to transmission efficiency. Therefore, improving transmission efficiency is particularly critical for the commercial vehicle electrification industry.

[0003] 2. The existing structural configuration can only meet the operating scenarios with small slopes and good road conditions. However, due to the complex terrain and diverse working conditions, new energy heavy trucks still face problems such as insufficient adaptability of the transmission system and high energy consumption in scenarios such as mountain transportation and mining operations.

[0004] 3. Adopt pure electric drive and single-axis drive. The single-axis drive mainly consists of a motor, a multi-speed gearbox, a drive shaft and other mechanical components, which will take up a lot of internal space. Moreover, since large commercial vehicles use a single motor, they need a high-power unit and the mass is very large. The size of the high-power and high-torque electric drive system is very large, which is not conducive to the chassis layout of heavy trucks.

[0005] 4. The existing multi-speed transmission adopts a single intermediate shaft, and the driven gear of the main box output shaft and the driving gear of the intermediate shaft are arranged in series one by one. The torque load of the single shaft is large, and there is a risk of transmission failure causing the transmission to fail to work effectively. Summary of the invention

[0006] The central drive box of a new energy heavy-duty truck and the shift control method thereof provided by the present invention realize multi-gear power output through a speed change combination at the power input end and the output end, thereby meeting the power requirements of the heavy-duty truck under various working conditions such as light load, heavy load, flat road, and ramp, and effectively ensuring that the motor operates in a high efficiency range under various working conditions to achieve better economy; multiple intermediate shafts are formed to balance the load, reduce the torque load of a single shaft, and improve the transmission efficiency; multiple intermediate shafts form a redundant design, reduce the risk of gearbox failure, improve the axial and radial space utilization of the drive box, and enhance the structural compactness of the drive box, so as to adapt to the chassis layout of the new energy heavy-duty truck.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: The central drive box of a new energy heavy-duty truck comprises a motor, an input shaft connected to the motor, an intermediate shaft meshing with the input shaft, and an output shaft, and is characterized in that it also comprises a single-stage planetary gear, a shift assembly 1 assembled on the input end of the single-stage planetary gear, and a shift assembly 2 assembled on the output shaft, the intermediate shaft is parallel to the input shaft and symmetrically distributed with the input shaft as the center, the planet carrier of the single-stage planetary gear is coaxially fixed with the output shaft, the single-stage planetary gear is connected to the input shaft or the intermediate shaft as the shift of the shift assembly 1 is performed, the single-stage planetary gear forms a high-torque and low-speed output or a low-torque and high-speed output as the shift of the shift assembly 2 is performed, and the input shaft, the single-stage planetary gear and the output shaft are coaxially aligned from front to back.

[0008] Preferably, the sun gear in the single-stage planetary gearbox is coaxially aligned with the input shaft, the shift assembly 1 is coaxially fixed with the sun gear, and the sun gear is connected to the input shaft or the intermediate shaft as the shift assembly 1 shifts.

[0009] Preferably, there are two intermediate shafts, the front end of the output shaft is fixedly connected to the planet carrier, and the rear end passes through the gear ring of the single-stage planetary gear.

[0010] Preferably, the gear shift assembly 2 is fixed to the ring gear and the drive box housing respectively, and the ring gear is locked by the drive box housing or locked into a whole with the planet carrier as the gear shift assembly 2 shifts.

[0011] Preferably, the input gear is coaxially fixed on the input shaft, the constant meshing gear and the low-speed driving gear are coaxially fixed on the intermediate shaft, the constant meshing gear is meshed with the input gear, and the low-speed driving gear is meshed with the shift assembly.

[0012] Preferably, a high-speed gear is coaxially fixed on the input shaft, and a shift assembly includes a shift gear coaxially fixed with the sun gear, a shift gear sleeve axially movably assembled on the shift gear, and a low-speed passive gear rotatably mounted on the sun gear center shaft through an idler sleeve, the low-speed driving gear is meshed with the low-speed passive gear, the shift gear sleeve is located between the high-speed gear and the low-speed passive gear, the shift gear sleeve moves to the left and combines with the high-speed gear, and moves to the right and combines with the low-speed passive gear.

[0013] Preferably, the second shift assembly includes a second shift gear assembled on the output shaft through a bearing and coaxially fixed with the ring gear, a second shift gear sleeve assembled on the second shift gear movably along the axial direction, a locking gear fixed on the drive box housing and a combining locking gear coaxially fixed on the output shaft, the second shift gear is located between the locking gear and the combining locking gear, the second shift gear sleeve moves to the left and combines with the locking gear to lock the ring gear on the drive box housing, and moves to the right and combines with the combining locking gear to lock the ring gear and the planetary carrier into a whole.

[0014] The above-mentioned shift control method of the central drive box of a new energy heavy-duty truck is characterized by: The first gear shift assembly is downshifted to connect the single-stage planetary gear with the intermediate shaft, and the second gear shift assembly is downshifted to form a high-torque and low-speed output of the single-stage planetary gear, and the output shaft outputs the first gear power; The first gear shift assembly is engaged in a low gear to connect the single-stage planetary gear with the intermediate shaft, and the second gear shift assembly is engaged in a high gear to form a low-torque and high-speed output of the single-stage planetary gear, and the output shaft outputs the second-gear power; The first gear shift assembly is engaged in high gear to connect the single-stage planetary gear with the input shaft, and the second gear shift assembly is engaged in low gear to form a high-torque and low-speed output of the single-stage planetary gear, and the output shaft outputs the third-gear power; The first gear shift component is engaged to connect the single-stage planetary gear with the input shaft, and the second gear shift component is engaged to form a low-torque and high-speed output of the single-stage planetary gear, and the output shaft outputs the fourth-speed power.

[0015] Preferably, shift assembly one shifting to a low gear means that shift sleeve one moves to the right and combines with the low-speed passive gear; shift assembly one shifting to a high gear means that shift sleeve one moves to the left and combines with the high-speed gear; shift assembly two shifting to a low gear means that shift sleeve two moves to the left and combines with the locking gear to lock the ring gear on the drive case housing, and shift sleeve two shifting to a high gear means that shift sleeve two moves to the right and combines with the locking gear to lock the ring gear and the planetary carrier into a whole.

[0016] The beneficial effects of the invention are: The central drive box of the new energy heavy-duty truck of the present invention has a single-stage planetary gearbox that is directly connected to the input shaft through a shift assembly 1 or indirectly connected to the input shaft through an intermediate shaft to form a speed change at the power input end, and forms a high-torque and low-speed output or a low-short and high-speed output through a shift assembly 2 to form a speed change at the power output end. The power multi-gear output is achieved through the speed change combination of the power input end and the output end, which meets the power requirements of the heavy-duty truck in various working conditions such as light load, heavy load, flat road, and ramp. Different power gears can be selected according to the driving conditions of the vehicle, which improves the climbing efficiency and reduces the energy consumption in high-speed working conditions, forming a multi-gear speed change of one motor. Compared with the solution of multi-motor and multi-gear speed change, the number of motors is reduced, thereby reducing the overall weight of the drive box, reducing its own load energy consumption, and improving the endurance. While ensuring the power of the vehicle Under this premise, the torque is output according to the working conditions, which effectively ensures that the motor runs in a high efficiency range under various working conditions and achieves better economy; a symmetrical arrangement of multiple intermediate shafts is adopted to form a multi-intermediate shaft load distribution, reduce the torque load of a single shaft, and improve the transmission efficiency. Multiple intermediate shafts form a redundant design, which can still ensure the effective output of power when a single shaft fails, and reduce the risk of gearbox failure. The input shaft, single-stage planetary gearbox and output shaft are coaxially aligned from front to rear, shift assembly one is assembled on the single-stage planetary gearbox, and shift assembly two is assembled on the output shaft, forming an arrangement in which the single-stage planetary gearbox is at the back and the motor is at the front, thereby improving the axial space utilization of the drive box, and the arrangement of multiple intermediate shafts plus planetary gearboxes improves the radial space utilization of the drive box, thereby improving the structural compactness of the drive box and adapting to the chassis layout of new energy heavy trucks. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the transmission structure of the central drive box of a new energy heavy-duty truck.

[0018] Figure 2 This is a schematic diagram of the first gear transmission of the central drive box of a new energy heavy-duty truck.

[0019] Figure 3 This is a schematic diagram of the second-gear transmission of the central drive box of a new energy heavy-duty truck.

[0020] Figure 4 This is a schematic diagram of the three-speed transmission of the central drive box of a new energy heavy-duty truck.

[0021] Figure 5 This is a schematic diagram of the four-speed transmission of the central drive box of a new energy heavy-duty truck. DETAILED DESCRIPTION

[0022] Combine the following Figures 1 to 5 The embodiments of the present invention are described in detail.

[0023] The central drive box of a new energy heavy-duty truck comprises a motor 1, an input shaft 2 connected to the motor 1, an intermediate shaft 3 meshing with the input shaft 2, and an output shaft 4, and is characterized in that it also comprises a single-stage planetary row 5, a shift assembly 1 6 assembled on the input end of the single-stage planetary row 5, and a shift assembly 2 7 assembled on the output shaft 4, the intermediate shaft 3 is parallel to the input shaft 2 and symmetrically distributed with the input shaft 2 as the center, the planet carrier 51 of the single-stage planetary row 5 is coaxially fixed with the output shaft 4, the single-stage planetary row 5 is connected to the input shaft 2 or the intermediate shaft 3 as the shift of the shift assembly 1 6, the single-stage planetary row 5 forms a high-torque and low-speed or low-torque and high-speed output as the shift of the shift assembly 2 7, and the input shaft 2, the single-stage planetary row 5 and the output shaft 4 are coaxially aligned from front to back.

[0024] In the central drive box of the new energy heavy-duty truck described above, the single-stage planetary gear 5 is directly connected to the input shaft 2 through the shifting assembly 1 6 or indirectly connected to the input shaft 2 through the intermediate shaft 4, forming a speed change at the power input end, and forming a high-torque low-speed or low-short high-speed output through the shifting assembly 2 7, forming a speed change at the power output end, and realizing power multi-gear output through the speed change combination of the power input end and the output end, meeting the power requirements of heavy-duty trucks in various working conditions such as light load, heavy load, flat road, and ramp. Different power gears can be selected according to the driving conditions of the vehicle, so as to improve the climbing efficiency and reduce the energy consumption in high-speed working conditions, forming a one-motor multi-gear speed change, and reducing the number of motors compared to the multi-motor multi-gear speed change solution, thereby reducing the overall weight of the drive box, reducing its own load energy consumption, and improving the endurance. On the premise of ensuring the power of the vehicle Under the premise, the torque is output according to the working conditions, which effectively ensures that the motor runs in a high efficiency range under various working conditions and achieves better economy; a symmetrical arrangement of multiple intermediate shafts is adopted to form a multi-intermediate shaft load balance, reduce the single-shaft torque load, and improve the transmission efficiency. Multiple intermediate shafts form a redundant design, which can still ensure the effective output of power when a single shaft fails, and reduce the risk of gearbox failure. The input shaft 2, the single-stage planetary gear 5 and the output shaft 4 are coaxially aligned from front to rear, the shift component 1 6 is assembled on the single-stage planetary gear 5, and the shift component 2 7 is assembled on the output shaft 4, forming an arrangement in which the single-stage planetary gear 5 is at the rear and the motor 1 is at the front, thereby improving the axial space utilization of the drive box, and the arrangement of multiple intermediate shafts plus planetary gears improves the radial space utilization of the drive box, thereby improving the structural compactness of the drive box and adapting to the chassis layout of new energy heavy trucks.

[0025] The sun gear 52 in the single-stage planetary row 5 is coaxially aligned with the input shaft 2, and the shift assembly 16 is coaxially fixed with the sun gear 52. The sun gear 52 is connected to the input shaft 2 or the intermediate shaft 3 as the shift assembly 16 is shifted. The shift assembly 16 shifts the sun gear 52 to directly connect with the input shaft 2, and the input shaft 2 directly transmits the power of the motor 1 to the single-stage planetary row 5, or connects the sun gear 52 to the intermediate shaft 3, so that the sun gear 5 is indirectly connected to the input shaft 2 through the intermediate shaft 3. The power of the motor 1 is transmitted to the single-stage planetary row 5 after the gears between the input shaft 2 and the intermediate shaft 3 cooperate to reduce the torque and increase the torque. Therefore, when the sun gear 52 is directly connected to the input shaft 2, the power transmitted to the single-stage planetary row 5 has a higher speed and a lower torque, while when the sun gear 52 is indirectly connected to the input shaft 2 through the intermediate shaft 3, the power transmitted to the single-stage planetary row 5 has a lower speed and a higher torque. Therefore, the speed change of the power input end can be achieved by replacing the shift assembly 16.

[0026] There are two intermediate shafts 3, the front end of the output shaft 4 is fixedly connected to the planet carrier 51, and the rear end passes through the gear ring 53 of the single-stage planetary gear 5. The two intermediate shafts 3 are equally loaded, reducing the torque load of the single shaft, improving the transmission efficiency, and forming a redundant design, which can still ensure the effective output of power under the failure of a single shaft and reduce the risk of gearbox failure. At the same time, the weight of the drive box is controlled by controlling the number of intermediate shafts 3 to avoid excessive self-load and increased energy consumption due to too many intermediate shafts 3. The output shaft 4 is fixedly connected to the planet carrier and passes through the gear ring 53, which can reduce the axial space occupied, improve the compactness of the structure, and thus reduce the axial size of the drive box.

[0027] Among them, the gear shift assembly 2 7 is fixed to the ring gear 53 and the drive box housing 8 respectively, and the ring gear 53 is locked by the drive box housing 8 or locked as a whole with the planet carrier 51 as the gear shifting assembly 2 7 is performed. When the ring gear 53 is locked by the drive box housing 8, the power of the single-stage planetary gear 5 is input by the sun gear, and is output through the planet carrier 51 after being decelerated by the planetary gear, the planet carrier and the ring gear, forming a low-speed and high-torque power output. When the ring gear 53 and the planet carrier 51 are locked as a whole, the planetary gear directly drives the ring gear and the planet carrier to rotate synchronously, forming a high-speed and low-torque direct driving force output. Therefore, the high-speed and low-torque or low-speed and high-torque power output of the single-stage planetary gear 5 is formed by the gear shifting of the gear shift assembly 2 7, and the speed change of the power output end is realized.

[0028] Among them, the input gear 21 is coaxially fixed on the input shaft 2, the constant meshing gear 31 and the low-speed driving gear 32 are coaxially fixed on the intermediate shaft 3, the constant meshing gear 31 meshes with the input gear 21, and the low-speed driving gear 32 meshes with the shift assembly 1 6. The gears of the intermediate shaft 3 and the input shaft 2 cooperate to form a power deceleration of the input end. When the shift assembly 1 6 shifts gears to connect the sun gear 52 with the intermediate shaft 3, the power of the input shaft 2 is transmitted to the sun gear via the input gear 21, the constant meshing gear 31, the low-speed driving gear 32 and the shift assembly 1 6. During the transmission process, the input power is decelerated and torque is increased. When the shift assembly 1 shifts gears to directly connect the sun gear 52 with the input shaft 2, the power of the input shaft 2 is directly transmitted to the sun gear 52 without deceleration.

[0029] Among them, the high-speed gear 22 is coaxially fixed on the input shaft 2, and the shift assembly 6 includes a shift gear 61 coaxially fixed with the sun gear 52, a shift gear sleeve 62 axially movably assembled on the shift gear 61, and a low-speed passive gear 63 rotatably mounted on the central axis of the sun gear 52 through an idler sleeve, the low-speed driving gear 32 is meshed with the low-speed passive gear 63, the shift gear sleeve 62 is located between the high-speed gear 22 and the low-speed passive gear 63, the shift gear sleeve 62 moves to the left and combines with the high-speed gear 22, and moves to the right and combines with the low-speed passive gear 63. When the shifting gear sleeve 1 62 is combined with the high-speed gear 22, the input shaft 2 directly drives the sun gear 52 to rotate, and the power does not pass through the intermediate shaft. The power input to the sun gear 52 has a higher speed and a lower torque. When the shifting gear sleeve 1 62 is combined with the low-speed driven gear 63, the power of the input shaft 2 is transmitted to the shifting gear sleeve 1 62, the shifting gear 61 and the sun gear 52 via the input gear 21, the constant meshing gear 31, the low-speed driving gear 32 and the low-speed driven gear 63. The power is decelerated via the intermediate shaft, and the power input to the sun gear 52 has a lower speed and a higher torque.

[0030] Among them, the shift assembly 2 7 includes a shift gear 2 71 assembled on the output shaft 4 through a bearing and coaxially fixed with the ring gear 53, a shift gear sleeve 2 72 assembled on the shift gear 2 71 axially movably, a locking gear 73 fixed on the drive box housing 8 and a combining locking gear 74 coaxially fixed on the output shaft 4, the shift gear 2 71 is located between the locking gear 73 and the combining locking gear 74, the shift gear sleeve 2 72 moves to the left and combines with the locking gear 73 to lock the ring gear 53 on the drive box housing 8, and moves to the right and combines with the combining locking gear 74 to lock the ring gear 53 and the planetary carrier 51 into a whole. If the shifting sleeve 2 72 is combined with the locking gear 73 to lock the ring gear 53, the power of the single-stage planetary row 5 is input from the sun gear 52 to the planet carrier 21 for output, forming a large speed ratio deceleration and torque increase, forming a low-speed and high-torque output of power; if the shifting sleeve 2 72 is combined with the locking gear 74, the planet carrier 52 and the ring gear 53 are locked as a whole, the power of the single-stage planetary row 5 is input from the sun gear 52, and the planetary gear directly drives the ring gear and the planet carrier to rotate synchronously, forming only a small speed ratio deceleration between the sun gear and the planetary gear, forming a high-speed and low-torque output of power.

[0031] like Figure 1As shown, the initial position of the shifting gear sleeve 1 62 is not combined with the high-speed gear 22 and the low-speed passive gear 63. At this time, the shifting gear sleeve 1 62 is in a neutral position, the input shaft 2 is separated from the sun gear 52, the power of the input shaft 2 will not be transmitted to the sun gear, and no power output can be formed. The initial position of the shifting gear sleeve 2 72 is not combined with the high-speed gear 22 and the low-speed passive gear 63. At this time, the shifting gear sleeve 2 72 is in a neutral position. Since the gear ring 53 is fixed to the shifting gear 2 72 and the shifting gear 2 71 can rotate on the output shaft 4, if the sun gear 52 drives the planetary gear to move, since the gear ring 53 can rotate relative to the output shaft 4, the planetary gear can only rotate by itself and will not drive the planet carrier 51 to rotate. , the power of the sun gear 52 will not be transmitted to the output shaft 4, and no power output can be formed. Therefore, when the shift assembly 1 6 and the shift assembly 2 7 are both in the neutral position, there is no power output; when the shift gear sleeve 1 62 is combined with the low-speed passive gear 63 and the shift gear sleeve 2 72 is combined with the locking gear 73, the power of the motor 1 is input to the sun gear after being reduced by the cooperation of the input shaft and the intermediate shaft, and is input to the output shaft 4 through the large speed ratio reduction of the single-stage planetary gear 5. The output shaft 4 has the lowest speed and the highest torque, forming a first gear power, which is suitable for heavy trucks and heavy-load slope conditions; when the shift gear sleeve 1 62 is combined with the low-speed passive gear 63 and the shift gear sleeve 2 72 is combined with the combined locking gear 74 ... The power is input to the sun gear after being reduced in speed by the cooperation of the input shaft and the intermediate shaft. Since the ring gear and the planetary carrier are locked as a whole, the power is directly driven to the output shaft 4 after being reduced in speed by a small speed ratio only between the sun gear and the planetary gears. The speed of the output shaft 4 is higher than that of the first gear power, and the torque is lower than that of the first gear power, forming a second gear power, which is suitable for heavy trucks and heavy-load flat road conditions; when the shift gear 1 62 is combined with the high-speed gear 22 and the shift gear sleeve 2 72 is combined with the locking gear 73, the power of the motor 1 is directly transmitted to the sun gear through the input shaft 2, and is input to the output shaft 4 through the large speed ratio reduction of the single-stage planetary row 5. The speed of the output shaft 4 is higher than that of the second gear power, and the torque is lower than that of the second gear power, forming a third gear power. force, which is suitable for heavy trucks with light load and slope conditions; when the shift gear 62 is combined with the high-speed gear 22 and the shift gear sleeve 72 is combined with the locking gear 74, the power of the motor is directly transmitted to the sun gear via the input shaft 2. Since the ring gear and the planetary carrier are locked as a whole, the power is only reduced by a small speed ratio between the sun gear and the planetary gears and then directly driven to the output shaft 4. The speed of the output shaft 4 is higher than that of the third gear power, and the torque is lower than that of the third gear power, forming a fourth gear power, which is suitable for heavy trucks with light load and flat road conditions, and meets the power requirements of heavy trucks in various working conditions such as light load, heavy load, flat road, and slope. Different power gears can be selected according to the driving conditions of the vehicle to improve climbing efficiency and reduce energy consumption in high-speed conditions.

[0032] The above-mentioned shift control method of the central drive box of a new energy heavy-duty truck is characterized by: The shift assembly 1 6 is downshifted to connect the single-stage planetary gear 5 to the intermediate shaft 3, and the shift assembly 2 7 is downshifted to form a high-torque and low-speed output of the single-stage planetary gear 5, and the output shaft 4 outputs the first gear power; The shift assembly 1 6 is put into low gear to connect the single-stage planetary gear 5 with the intermediate shaft 3, and the shift assembly 2 7 is put into high gear to form a low-torque and high-speed output of the single-stage planetary gear 5, and the output shaft 4 outputs the second-gear power; The shift assembly 1 6 is engaged in high gear to connect the single-stage planetary gear 5 to the input shaft 2, and the shift assembly 2 7 is engaged in low gear to form a high-torque and low-speed output of the single-stage planetary gear 5, and the output shaft 4 outputs the third-gear power; The shift assembly 1 6 is shifted into high gear to connect the single-stage planetary gear 5 to the input shaft 2, and the shift assembly 2 7 is shifted into high gear to form a low-torque and high-speed output of the single-stage planetary gear 5, and the output shaft 4 outputs the fourth-speed power.

[0033] The above shift control method, through the shifting of shift component one and shift component two, forms a first gear power suitable for heavy truck heavy load slope conditions, a second gear power suitable for heavy truck heavy load flat road conditions, a third gear power suitable for heavy truck light load slope conditions, and a fourth gear power suitable for heavy truck light load flat road conditions, which meets the power requirements of heavy trucks in various working conditions such as light load, heavy load, flat road, and slope. Different power gears can be selected according to the vehicle's driving conditions to improve climbing efficiency and reduce energy consumption in high-speed conditions.

[0034] Among them, the shift component 16 shifting to a low gear means that the shift gear sleeve 1 62 moves to the right and combines with the low-speed passive gear 63; the shift component 16 shifting to a high gear means that the shift gear sleeve 1 62 moves to the left and combines with the high-speed gear 22; the shift component 27 shifting to a low gear means that the shift gear sleeve 2 72 moves to the left and combines with the locking gear 73 to lock the ring gear 53 on the drive case housing 8, and the shift gear sleeve 2 7 shifting to a high gear means that the shift gear sleeve 2 72 moves to the right and combines with the locking gear 74 to lock the ring gear 53 and the planetary carrier 51 into a whole.

[0035] When both the shift assembly 1 6 and the shift assembly 2 7 are in low gear, the power of the motor 1 is input to the sun gear after being decelerated by the cooperation of the input shaft and the intermediate shaft, and is input to the output shaft 4 through the large speed ratio deceleration of the single-stage planetary row 5. The output shaft 4 has the lowest speed and the highest torque, forming a first gear power, which is suitable for heavy trucks and heavy loads on slope conditions; when the shift assembly 1 6 is in low gear and the shift assembly 2 7 is in high gear, the power of the motor is input to the sun gear after being decelerated by the cooperation of the input shaft and the intermediate shaft. Since the ring gear and the planetary carrier are locked as a whole, the power is only directly driven and input to the output shaft 4 after forming a small speed ratio deceleration between the sun gear and the planetary gear. The speed of the output shaft 4 is higher than the first gear power, and the torque is lower than the first gear power, forming a second gear power, which is suitable for heavy trucks and heavy loads on flat roads; when the shift assembly 1 6 is in high gear and the shift assembly 2 7 is in high gear, the power of the motor is input to the sun gear after being decelerated by the cooperation of the input shaft and the intermediate shaft. Since the ring gear and the planetary carrier are locked as a whole, the power When component two is in low gear, the power of motor 1 is directly transmitted to the sun gear via input shaft 2, and is input to output shaft 4 through large speed ratio reduction of single-stage planetary gear 5. The speed of output shaft 4 is higher than that of second gear power, and the torque is lower than that of second gear power, forming third gear power, which is suitable for heavy truck and light load slope conditions; when shift component one 6 and shift component two 7 are both in high gear, the power of motor is directly transmitted to sun gear via input shaft 2. Since the ring gear and the planet carrier are locked as a whole, the power is only directly driven to output shaft 4 after small speed ratio reduction between sun gear and planet gear. The speed of output shaft 4 is higher than that of third gear power, and the torque is lower than that of third gear power, forming fourth gear power, which is suitable for heavy truck and light load flat road conditions. Shift component one 6 and shift component two 7 are used to realize fast switching of gears, simplifying the speed control process.

[0036] The above is a complete description of the technical solutions of the embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the described embodiments are only part of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

Claims

1. A central drive box for a new energy heavy truck, comprising a motor, an input shaft connected to the motor, an intermediate shaft meshing with the input shaft, and an output shaft, characterized in that: It also includes a single-stage planetary gear, a shift assembly 1 assembled on the input end of the single-stage planetary gear, and a shift assembly 2 assembled on the output shaft. The intermediate shaft is parallel to the input shaft and is symmetrically distributed with the input shaft as the center. The planet carrier of the single-stage planetary gear is coaxially fixed to the output shaft. The single-stage planetary gear is connected to the input shaft or the intermediate shaft as the shift assembly 1 shifts. The single-stage planetary gear forms a high-torque and low-speed output or a low-torque and high-speed output as the shift assembly 2 shifts. The input shaft, the single-stage planetary gear and the output shaft are coaxially aligned from front to back.

2. The central drive box of a new energy heavy truck according to claim 1 is characterized in that: The sun gear in the single-stage planetary gear is coaxially aligned with the input shaft, the shift assembly 1 is coaxially fixed with the sun gear, and the sun gear is connected to the input shaft or the intermediate shaft as the shift assembly 1 shifts gears.

3. The central drive box of a new energy heavy truck according to claim 2 is characterized in that: There are two intermediate shafts, the front end of the output shaft is fixedly connected to the planet carrier, and the rear end passes through the gear ring of the single-stage planetary gear.

4. The central drive box of a new energy heavy truck according to claim 2 is characterized in that: The gear shift assembly 2 is fixed to the ring gear and the drive box housing respectively, and the ring gear is locked by the drive box housing or locked into a whole with the planet carrier as the gear shift assembly 2 is shifted.

5. The central drive box of a new energy heavy truck according to claim 1 is characterized in that: The input gear is coaxially fixed on the input shaft, and the constant meshing gear and the low-speed driving gear are coaxially fixed on the intermediate shaft. The constant meshing gear meshes with the input gear, and the low-speed driving gear meshes with the shifting assembly.

6. The central drive box of a new energy heavy truck according to claim 5 is characterized in that: The high-speed gear is coaxially fixed on the input shaft, and the shift assembly 1 includes a shift gear 1 coaxially fixed with the sun gear, a shift gear sleeve 1 axially movable and assembled on the shift gear 1, and a low-speed passive gear rotatably mounted on the sun gear center shaft through an idler sleeve, the low-speed driving gear is meshed with the low-speed passive gear, the shift gear sleeve 1 is located between the high-speed gear and the low-speed passive gear, the shift gear sleeve 1 moves to the left and combines with the high-speed gear, and moves to the right and combines with the low-speed passive gear.

7. The central drive box of a new energy heavy truck according to claim 6 is characterized in that: The shift assembly 2 includes a shift gear 2 assembled on the output shaft through a bearing and coaxially fixed with the ring gear, a shift gear sleeve 2 assembled on the shift gear 2 and movably along the axial direction, a locking gear fixed on the drive box housing and a combined locking gear coaxially fixed on the output shaft. The shift gear 2 is located between the locking gear and the combined locking gear. The shift gear sleeve 2 moves to the left and combines with the locking gear to lock the ring gear on the drive box housing, and moves to the right and combines with the combined locking gear to lock the ring gear and the planetary carrier into a whole.

8. The shift control method of the central drive box of a new energy heavy truck according to any one of claims 1 to 7, characterized in that: The first gear shift assembly is downshifted to connect the single-stage planetary gear with the intermediate shaft, and the second gear shift assembly is downshifted to form a high-torque and low-speed output of the single-stage planetary gear, and the output shaft outputs the first gear power; The first gear shift assembly is engaged in a low gear to connect the single-stage planetary gear with the intermediate shaft, and the second gear shift assembly is engaged in a high gear to form a low-torque and high-speed output of the single-stage planetary gear, and the output shaft outputs the second-gear power; The first gear shift assembly is engaged in high gear to connect the single-stage planetary gear with the input shaft, and the second gear shift assembly is engaged in low gear to form a high-torque and low-speed output of the single-stage planetary gear, and the output shaft outputs the third-gear power; The first gear shift component is engaged to connect the single-stage planetary gear with the input shaft, and the second gear shift component is engaged to form a low-torque and high-speed output of the single-stage planetary gear, and the output shaft outputs the fourth-speed power.

9. The shift control method of the central drive box of a new energy heavy truck according to claim 8 is characterized in that: Shift assembly one shifting down gear means that shift sleeve one moves to the right and combines with the low-speed passive gear; shift assembly one shifting up gear means that shift sleeve one moves to the left and combines with the high-speed gear; shift assembly two shifting down gear means that shift sleeve two moves to the left and combines with the locking gear to lock the ring gear on the drive case housing, and shift sleeve two shifting up gear means that shift sleeve two moves to the right and combines with the locking gear to lock the ring gear and the planetary carrier into a whole.

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